Aneurysmal bone cyst: diagnostic differences with telangiectatic osteosarcoma. A case report

Abstract

Introduction: Symptoms, signs, imaging and histological findings of aneurysmal bone cyst (ABC) and telangiectatic osteosarcoma (TO) are similar, which makes them one of the most difficult differential diagnoses.

Case presentation: A 19-year-old woman attended the emergency department of a quaternary care hospital in Bogotá, Colombia, due to pain in the left hip. A lytic lesion in the femur was identified and the patient was referred to the outpatient clinic. Three days later, the patient returned to the emergency department with left hip pain and functional disability. By means of X-ray and MRI, a transcervical fracture of the hip was identified at the site of the lytic lesion, so the presence of ABC or TO was suspected. The patient was taken to surgery and a frozen section biopsy was performed, confirming the diagnosis of ABC. Consequently, curettage and reaming of the lesion were undertaken, followed by reduction and fixation of the fracture using the DHS (dynamic hip screw) system, and application of bone grafting and bone cement. Four days after the procedure, the patient was discharged. A follow-up at eight months showed complete recovery of hip functionality and absence of pain.

Conclusion: In patients with a high suspicion of this type of bone lesions, it is important to perform a histopathological study to confirm the diagnosis of ABC or TO, and to establish an adequate and timely treatment, which will undoubtedly contribute to a better prognosis, particularly in terms of survival.